When jobs are executed for prescribed operations in a computer system operating on a large-scale network or the like, the jobs are scheduled and are then assigned to resources (nodes).
In general, jobs are assigned on the basis of the amount of resources (the number of nodes, the memory capacities of the nodes, and others) that are needed to execute the jobs and time restrictions on when the jobs need to be completed.
For example, one of techniques related to the job assignment is that an agent which frequently communicates with an agent running on a node is moved to the node.
Further, for example, there is a technique in which an operating node is taken as an imaginary heat source, a lowest temperature free node among free nodes placed around the heat source is taken as a center node, and a node close to the center node is selected.
Still further, there is a technique of searching a plurality of nodes for free resources that are free during a time period between the current time and the scheduled start time of an already assigned job, and assigning a job to the found free resources.
Please see, for example, Japanese Laid-open Patent Publication Nos. 2007-293761, 2011-227747, and 2015-194923.
When a job is assigned to nodes, for example, as many free nodes as needed to execute the job are searched for. However, if free nodes and busy nodes executing other jobs exist (this state is called a fragmented state), communication between nodes may be unfeasible, and this may hold off on the assignment of the job to the free nodes.
To deal with this, in the case where the fragmented state occurs, jobs are migrated so that free nodes are placed together, and jobs are assigned to the free nodes in a region that has more free nodes as a result of the migration. In this connection, the migration is a technique in which a job executed by a node is moved to another node for the execution.
However, if the migration itself takes time to complete, the migration does not lead to an improvement in the overall operating rate of the system.